Production of a ferrous composition and article therefor



Patented May 30, 1950 PRUDU'lTION OF A FEBROUS COMPOSITION AND ARTICLE THEREFOR Norman E. Tisdale, Pittsburgh, and Emil August Lucas, Washington, Pa., asslgnors to Molybdenum Corporation of America, New York, N. 2., a corporation of Delaware No Drawing. Application mi." 1?, 19%, Serial No. 2.95s

16 Claims. (CL 75-129) The invention relates to a method for the introduction of boron and other alloying materials, especially those which are readily oxidizable, into a ferrous base and to a product therefor. More particularly, it pertains to an incased boron composition for incorporation into molten iron or steel, and includes correlated improvements and discoveries whereby the incorporation of an alloyin material with iron is distinctly facilitated.

An object of the invention is to provide a method in accordance with which an alloying material may be easily introduced into, and thoroughly and uniformly distributed through a molten ferrous base material.

A further object of the invention is the provision of a method which gives a high recovery of the alloying material, particularly boron, i. e., the boron enters into the composition of the ferrous base material and is not essentially dissipated by volatilization or otherwise.

An additional object of the invention is to provide an article of manufacture that can be readily and economically produced, and by the use of which the introduction of an alloying material into a ferrous base material may be effectlvely accomplished.

Still another object of the invention is to provide an article of manufacture containing an alloying material through the utilization of which it may be incorporated with molten ferrous base material in definite units, and graduated as may be desired.

A more particular object of the invention is to provide as an article of manufacture a boron composition such as a ferro boron or other boron containing composition incased in a metal selected from the group consisting of aluminum and magnesium.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the several steps and the relation of one or moreof such steps with respect to each of the others, and the article possessing the features, properties, and the relation of elements, which are exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims. I i

In the practice of the invention, a readily oxidizable alloying material containing a metal selected from the group consisting of boron, vanadium, titanium, zirconium and beryllium. usually as the term alloys, may be introduced into a ferrous base material by incorporating, for example, a suitable boron composition incased in a metal selected from the group consisting of aluminum and magnesium, with a molten ferrous base material, as an iron. It will be realized that various steels, as the structural and the tool steels are merely one form of molten iron. Desirably the boron composition, which will be taken to illustrate the invention, may be a farm boron which may suitably contain from about 10% to about 14% of boron. However, if a product of relatively high boron content is desired, a nineteen percent ferro boron may be employed. A term alloy, as ferro boron, is preferred since it readily enters into and is distributed through the molten iron. The incasement of the boron composition in a metal may be effected by producing a block of the metal having a cavity therein, placing the boron composition within the cavity, and then closing or sealing the cavity by means of a closure, which may be a metal or a combustible substance as wood, cardboard and. the like, and preferably is, iron or steel. Further, the cavitied block may be separate, or a series thereof may be joined together at the base or otherwise by means of a web of the metal.

In order to introduce the boron, for example, into a molten iron or steel, one or more of the cavitied blocks may be introduced into the bath or into the ladle. Satisfactory results have been obtained by having each cavitied metal block contain that amount of term boron which is sufliclent for the introduction of the desired amount of boron into one ton of the iron or steel. In the event that it were to be desired to introduce a larger amount of boron, it will be realized that it will be necessary only to incorporate additional blocks containing the incased boron composition. A form which has been found to be well adapted for incorporation of the boron is a cavitied block or cup of aluminum which may be semispherical or rectangular in shape, and has a cavity of sumcient size toreceive the amount of term boron which will serve to treat one ton of steel. The closure may be effected by means of an iron, steel, cardboard or wood disc.

As an illustrative embodiment of a manner in which the invention may be practiced, the following examples are given: The parts are by weight.

EXAMPLE I A basic open hearth furnace was charged with parts of molten pig iron and 215 parts of 3 scrap metal. During the furnacing operation. the following materials were added:

Material: 1 1 Parts limestone 10.0 Lime 19.2 Roasted dolomite 7.5

, Sillco manganese 1.2 Form manganese 6.0 Ferro silicon (50%) 1.4 Molybdenum trioxide 0.72

Material: Percent Carbon .28 Manganese 1.74 Phosphorus .019 Sulphur .018

Silicon .19 Molybdenum .17 Boron .003

and the remainder iron.

This procedure leads to a uniform distribution of the boron as is evidenced in the following tab-. ulation showing the hardness or hardenability by the Jominy test.

Rockwell C hardness readings Bottom of Top of Last Distance in First ingot Ingot Sixteenths The boron content may range from .0005 to .008 for structural steels and may be up to 1% for tool steels.

EXAMPLE II A nickel molybdenum steel was prepared by charging an open hearth furnace-again the amounts actually used being divided by 1000, for simplification-with Material: Parts Hot metal 100.0 Heavy scrap #2 11.8 3 nickel scrap 65.5

. Punchings 23.2

Nickel chromium scrap containing about 1.5 nickel and chromium- 0.5% 20.0 3%% nickel billets 25.0 The following materials were added during the furnacing operation:

To the ladle there were added:

Material: Parts Silicon 1.1

v Aluminum 0.1 l Ferro boron in the form of aluminumferro boron cups 0.062

The additions of the ladle' were made in the foregoing order with the term boron being introduced immediately after the aluminum and thrown into the ladle at different locations. The boron sank beneath the surface at once and was readily absorbed. The finished product had the following composition:

Per cent Carbon 01 Manganese 0.48 Phosphorus 0.010 Sulphur 0.024

20 Nickel 1.65

Chromium 0.08 Molybdenum 0.22 Copper 0.09 Boron 0.0028

with the remainder being iron.

The iron and steel may be made by a. conventional method, and suitably by a method which will produce a clean, degassified commercial product in the molten state. The aluminum blocks or cups containing a boron composition, or other alloying material, may be added to the bath prior to pouring or to the ladle during or immediately after pouring. When added to the bath, care should be taken that the boron passes quickly through the slag.

Furthermore, theforegoing procedure in accordance with which boron may be added to a molten iron as a steel leads to a high recovery of the boron and to a uniform distribution throughout the molten mass as is evidenced by the tabulation given above. This tabulation, as stated, sets forth the results of a Jominy hardenability test and shows that the effect of boron on hardenability is uniform from the first to the last ingot.

Since certain changes in carrying out the above process, and certain modifications in the article which embody the invention may be made without departing from its scope, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A method for the introduction of boron into an iron which comprises incorporating a farm boron composition incased in a metal selected from the group consisting of aluminum and magnesium into a molten iron subsequent to substantial deoxidation thereof.

2. A method for the introduction of boron into an iron which comprises incorporating a ferro boron containing from about 10% to about 19% of boron incased in a metal selected from the group consisting of aluminum and magnesium into a molten iron subsequent to substantial deoxidation thereof.

3. A method for the introduction of boron into an iron which comprises incorporating a ferro boron containing from about to about 14% of boron incased in a metal selected from the group consisting of aluminum and magnesium into a molten iron subsequent to substantial de oxidation thereof.

4. A method for the introduction of boron into a steel which comprises incorporating a boron composition incased in a metal selected from the group consisting of aluminum and magnesium into a molten steel subsequent to substantial deoxidation thereof.

5. A method for the introduction of boron into a steel which comprises incorporating a ferro boron composition incased in a metal selected from the group consisting of aluminum and magnesium into a molten steel subsequent to substantial deoxidation thereof.

6. As an article of manufacture a boron composition incased in a metal selected from the group consisting of aluminum and magnesium.

7. As an article of manufacture a ferro boron incased in a metal selected from the group consisting of aluminum and magnesium.

8. As an article of manufacture a ferro boron containing from about 10% to about 19% of boron incased in a. metal selected from the group consisting of aluminum and magnesium.

9. As an article of manufacture a, cavitied metal selected from the group consisting of aluminum and magnesium having a readily oxidiz-- able alloying material containing a metal selected from the group consisting of boron, vanadium, titanium, zirconium and beryllium within the cavity, and said cavity being closed.

10. As an article of manufacture a cavitied metal selected from the group consisting of aluminum and magnesium having a boron composition within the cavity, and said cavity being closed.

11. As an article of manufacture a cavitied metal selected from the group consisting of aluminum and magnesium having a boron composition within the cavity, and said cavity being closed by a metal closure.

12. As an article of manufacture a cavitied metal selected from the group consisting of alu- 6 minum and magnesium having a ferro boron within the cavity, and said cavity being closed by a metal closure.

13. As an article of manufacture a metal selected from the group consisting of aluminum and magnesium in the form of a cavitied block having a ferro boron within the cavity, and said cavity being closed by an iron closure.

14. As an article of manufacture a metal selected from the group consisting of aluminum and magnesium in the form of a cavitied block having a term boron containing from about 10% to about 19% of boron, within the cavity, and said cavity being closed by an iron closure.

15. A method for the introduction of an alloying material into a ferrous base which comprises incorporating a readily oxidizable alloying material containing a metal selected from the group consisting of boron, vanadium, titanium, zirconium and beryllium incased in a metal selected from the group consisting of aluminum and magnesium, into a molten ferrous base subsequent to substantial deoxidation thereof.

16. As an article of manufacture a readily oxidizable alloying material containing a metal selected from the group consisting of boron, vanadium, titanium, zirconium and beryllium incased in a metal selected from the group consisting of aluminum and magnesium.

NORMAN F. TISDALE. EMIL AUGUST LUCAS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Transactions, American Institute of Mining and Metallurgical Engineers, vol. 111, 1934, page 322. Published by the A. I. M. E., New York. 

1. A METHOD FOR THE INTRODUCTION OF BORON INTO AN IRON WHICH COMPRISES INCORPORATING A FERRO BORON COMPOSITION INCASED IN A METAL SELECTED FROM THE GROUP CONSISTING OF ALUMINUM AND MAGNESIUM INTO A MOLTEN IRON SUBSEQUENT TO SUBSTANTIAL DEOXIDATION THEREOF. 